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Vitamin C

Vitamin ·Exploratory record · not publication-reviewed ·Updated September 28, 2026

A powerful antioxidant essential for collagen synthesis, immune function, and iron absorption. Humans cannot synthesize it and must obtain it from diet or supplements.

Evidence tier
Strong
Indexed sources
17 2004–2024
Interactions
0
Cost / month
$1.50 budget
Read the sources → Compare profiles
Publication status

Exploratory record, not a reviewed medical publication.

See the editorial and medical-review policies for the publication gate.

This generated database record has not completed a claim-level review by a qualified human medical reviewer. Bibliography links and evidence labels are not approval. The page remains available for reference and is excluded from search indexing.

In short

What the research says.

A quick, data-only summary. The full evidence, dosing, and sources are below.

Vitamin C is a vitamin most often used for immune support, collagen synthesis, antioxidant protection. NutriStack rates the overall evidence as strong. A typical adult dose is 500–2,000 mg daily, commonly taken as ascorbic acid or liposomal vitamin c for higher absorption. This profile indexes 17 sources.

What it's good for
  • Immune support6,10
  • Collagen synthesis15
  • Antioxidant protection15,1
  • Iron absorption16
  • Skin health15
What to watch for
  • GI upset at high doses
  • Diarrhea
  • Kidney stones (rare, at very high doses)
  • History of kidney stones (high doses)9
  • Hemochromatosis

The bottom line

Evidence rating strong. Most-documented uses: immune support, collagen synthesis, antioxidant protection. 17 sources indexed (2004–2024), with 0 interaction records on file.

The science

How it works, mechanistically.

Core mechanism

Acts as an electron donor, neutralizing free radicals. Required cofactor for prolyl and lysyl hydroxylases in collagen synthesis. Enhances non-heme iron absorption by reducing ferric iron to ferrous form. Supports immune cells including neutrophils and lymphocytes.

Class
Water-Soluble Vitamin
Found in food
Citrus fruits, Bell peppers, Strawberries
Low-status signs
Scurvy, Bleeding gums
Dosing

Dosing & protocol.

Common range
500–2,000 mg daily
Recommended form
Ascorbic acid or liposomal vitamin C for higher absorption

Water-soluble; split doses throughout day for better absorption1,3

Cost

What it actually costs.

Real-world pricing across three quality tiers. Assumes Ascorbic Acid.

BudgetBest value
$1.50 /mo
$0.05 per dose
Mid
$3.00 /mo
$0.10 per dose
Premium
$6.60 /mo
$0.22 per dose

Assumes about 500-1,000 mg/day. Plain ascorbic acid remains one of the best values unless GI tolerance is poor. Updated 2026-04-02.

From food

The same dose, as food.

How much you'd eat to match a supplemental dose.

500 mg vitamin C
About 1 red bell pepper plus 2 cups strawberries plus 1 kiwi

Food can easily cover modest vitamin C targets.

1,000 mg vitamin C
About 2 red bell peppers plus 3 cups strawberries

Higher supplemental-style doses are harder to match from food every day.

Safety

Full safety detail.

Side effects

  • GI upset at high doses
  • Diarrhea
  • Kidney stones (rare, at very high doses)

Contraindications

  • History of kidney stones (high doses)9
  • Hemochromatosis
Sources

Sources, by evidence tier.

Numbered references. Citations throughout the page link here.

Meta-analyses & systematic reviews

11

Reviews & position papers

5

Reference material

1
FAQ

Common questions.

Quick answers about Vitamin C, drawn from the data on this page.

What is Vitamin C?

A powerful antioxidant essential for collagen synthesis, immune function, and iron absorption. Humans cannot synthesize it and must obtain it from diet or supplements.

What is Vitamin C used for?

Commonly cited benefits of Vitamin C include: Immune support; Collagen synthesis; Antioxidant protection; Iron absorption; Skin health. NutriStack rates the overall evidence as strong.

What is a typical dose of Vitamin C?

A typical adult dose of Vitamin C is 500–2,000 mg daily. The commonly recommended form is Ascorbic acid or liposomal vitamin C for higher absorption. These are general ranges, not personalized advice; confirm the right dose with a clinician.

What are the side effects of Vitamin C?

Reported side effects include gi upset at high doses, diarrhea, kidney stones (rare, at very high doses). This is educational information; check with a healthcare professional before use.

How strong is the evidence for Vitamin C?

NutriStack rates this as Strong, meaning multiple high-quality meta-analyses or systematic reviews converge on the same finding. Full tier criteria are at https://nutristackapp.com/methodology/evidence-tiers.

Use this with your stack

Vitamin C in NutriStack.

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NutriStack is an informational and organizational tool, not a medical service, and not a substitute for professional advice. Always consult a qualified healthcare professional before starting, stopping, or changing any supplement or medication.